Field of the Invention
The present invention relates to a method for manufacturing a stop collar for a pipe fitting device and a stop collar manufactured by the same, and more particularly, to a method for manufacturing a stop collar for a pipe fitting device and a stop collar manufactured by the same wherein a raw material is machined sequentially through extrusion molding, heat treatment, cutting, and grinding, thus enabling a standardized stop collar to be produced in large quantities, and an elastic force is applied to the stop collar, thus providing easy fastening and repeatable uses and further preventing the pipe fitting device and connected pipes by the pipe fitting device from being damaged.
Background of the Related Art
Generally, two or more pipes are connected to each other by means of a simple connection part like an elbow or fitting, that is, a pipe fitting device, according to the construction conditions and the environments at the construction site.
The pipe fitting device is adapted to grasp pipes fitted to both sides or three directions of a body by means of ferrules moving by nuts and to connect the pipes with each other.
For example, Korean Utility Model Application Laid-open No. 2007-000500 discloses a pipe fitting device that basically includes a fitting body to which pipes are fitted, ferrules, and nuts and further has O-rings disposed on the inner peripheries of connection holes to which the pipes are connected and disposed on the inclined surfaces of the inner and outer peripheries of the connection holes, thus increasing the sealing effects thereof.
According to the conventional pipe fitting device, after the pipes are inserted into the fitting body, the nuts are tightened to grasp the pipes. At this time, however, it is hard to expect an amount of nut tightening, so that the nuts are loosely or excessively tightened, the pipes are deformed to cause the dangers of leakage.
So as to check the accurate amount of nut tightening, recently, stop collars (fitting rings) have been developed and used.
One example of conventional stop collars for a pipe fitting device is disclosed in Korean Patent Registration No. 10-1356612.
Another example is disclosed in Korean Patent Registration No. 10-0948403 suggesting a pipe fitting and a method for manufacturing a fitting ring for a pipe fitting.
The method for manufacturing a fitting ring for a pipe fitting includes the steps of: preparing a lower mold as an injection mold having a steel piece mounting portion protruding from the center of the inner surface thereof to support a ring-shaped steel piece and a ring molding space formed along the periphery of the steel piece mounting portion; preparing the ring-shaped steel piece as an insert coming into close contact with the periphery of the steel piece mounting portion of the lower mold; preparing an upper mold as an injection mold having a tail molding portion protruding on the center of the lower portion thereof in such a manner as to advance into the ring molding space of the lower mold and a sprue formed on one side thereof, through which a fused material is injected into the ring molding space of the lower mold; coupling the ring-shaped steel piece to the periphery of the steel piece mounting portion of the lower mold; coupling the lower mold to the upper mold so that the tail molding portion of the upper mold is introduced into the ring molding space of the lower mold; injecting the fused material into the sprue of the upper mold so as to introduce the fused material into the ring molding space of the lower mold; and cooling the fused material injection-molded through the upper mold and the lower mold at a normal temperature.
In more detail, the fused material as a rubber material is injected into the upper mold and the lower mold so as to obtain the molded product, and further, the ring-shaped steel piece is disposed on the inner surface of the molded product so as to enhance the strength of the fitting ring, thus preventing the breakage of the fitting ring while in use. Furthermore, the outer shape of the fitting ring is inclinedly formed to increase the contacted area with the pipe fitting device. However, the conventional fitting ring is made through the injection molding, thus making it impossible to conduct precise machining, and besides, it cannot be checked whether fitting nuts are loosely or excessively tightened. Of course, undesirably, the conventional fitting ring cannot be re-used.